常见控件的使用方法 TextView EditText Button Menu

这篇文章将给大家介绍TextView EditText Button Menu这几个控件的使用方法，同时在布局文件里面还有一个新的东西，线性布局，以及string.xml的使用，这里的string.xml是用来做国际化用的。

1、创建第一个Activity,ThridLessonDemo1.java

package com.example.helloworld;

import android.app.Activity;
import android.content.Intent;
import android.os.Bundle;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.EditText;
import android.widget.TextView;


public class ThridLessonDemo1 extends Activity {
 private EditText num1;
 private EditText num2;
 private TextView myTextView;
 private Button calculate;

 @Override
 protected void onCreate(Bundle savedInstanceState) {
  // TODO Auto-generated method stub
  super.onCreate(savedInstanceState);
  // 根据控件的ID来取得代表控件的对象
  setContentView(R.layout.thridfirst);
  num1 = (EditText) findViewById(R.id.Numo);
  num2 = (EditText) findViewById(R.id.Numt);
  myTextView = (TextView) findViewById(R.id.myTextView);
  calculate = (Button) findViewById(R.id.calculate);
  myTextView.setText(R.string.cy);
  calculate.setText(R.string.js);
  calculate.setOnClickListener(new myButtonListener());
 }

 class myButtonListener implements OnClickListener {

  public void onClick(View arg0) {
   // TODO Auto-generated method stub
   String v1 = num1.getText().toString();
   String v2 = num2.getText().toString();
   Intent intent = new Intent();
   intent.putExtra("num1", v1);
   intent.putExtra("num2", v2);
   intent.setClass(ThridLessonDemo1.this, ThridLessonDemo2.class);
   startActivity(intent);
  }

 }
 //当客户点击MENU按钮时调用该方法
 @Override
 public boolean onCreateOptionsMenu(Menu menu) {

  menu.add(0, 1, 1, R.string.ext);
  menu.add(0, 2, 2, R.string.about);

  // TODO Auto-generated method stub
  return super.onCreateOptionsMenu(menu);
 }
 //当客户点击菜单当中的某一个选项时，会调用该方法
 @Override
 public boolean onOptionsItemSelected(MenuItem item) {
  if (item.getItemId() == 1) {
   finish();
  }

  // TODO Auto-generated method stub
  return super.onOptionsItemSelected(item);
 }

}

2、创建第二个Activity,ThridLessonDemo2.java

package com.example.helloworld;

import android.app.Activity;
import android.content.Intent;
import android.os.Bundle;
import android.widget.TextView;


public class ThridLessonDemo2 extends Activity {

 private TextView resultView;

 @Override
 protected void onCreate(Bundle savedInstanceState) {
  // TODO Auto-generated method stub
  super.onCreate(savedInstanceState);
  setContentView(R.layout.thridsecond);
  resultView = (TextView) findViewById(R.id.resultView);
  Intent intent = getIntent();
  String num1 = intent.getStringExtra("num1");
  String num2 = intent.getStringExtra("num2");
  int _num1 = Integer.parseInt(num1);
  int _num2 = Integer.parseInt(num2);
  int result = _num1 * _num2;
  resultView.setText(result + "");
 }

}

3、创建第一个Activity的布局文件，thridfirst.xml

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    android:orientation="vertical" >

    <EditText
        android:id="@+id/Numo"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:inputType="number" />

    <TextView
        android:id="@+id/myTextView"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content" />

    <EditText
        android:id="@+id/Numt"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:inputType="number" />

    <Button
        android:id="@+id/calculate"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content" />

</LinearLayout>

4、创建第二个Activity的布局文件，thridsecond.xml

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    android:orientation="vertical" >

    <TextView
        android:id="@+id/resultView"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content" />

</LinearLayout>

5、修改res/values/strings.xml

<resources>

    <string name="app_name">HelloWorld</string>
    <string name="hello_world">Hello world!</string>
    <string name="menu_settings">Settings</string>
    <string name="title_activity_main">MainActivity</string>
 <string name="other">otherActivity</string>
 <string name="ok">确定</string>
 <string name="cy">乘以</string>
 <string name="js">计算</string>
 <string name="ext">退出</string>
 <string name="about">关于</string>
</resources>

6、注册这两个Activity

<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="com.example.helloworld"
    android:versionCode="1"
    android:versionName="1.0" >

    <uses-sdk
        android:minSdkVersion="4"
        android:targetSdkVersion="15" />

    <application
        android:icon="@drawable/ic_launcher"
        android:label="@string/app_name"
        android:theme="@style/AppTheme" >
        <activity
            android:name=".MainActivity"
            android:label="@string/title_activity_main" >
        </activity>
        <activity
            android:name=".SecondLessonDemo1"
            android:label="@string/other" >
        </activity>
        <activity
            android:name=".SecondLessonDemo2"
            android:label="dd" >
        </activity>
        <activity
            android:name=".ThridLessonDemo1"
            android:label="dd2" >
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />

                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>
        <activity
            android:name=".ThridLessonDemo2"
            android:label="dd3" >
        </activity>
    </application>

</manifest>